冻土区管道弯曲应变及位移监测方法

Bending strain and displacement monitoring method for pipelines in permafrost zones

针对冻土区管道易受融沉、冻胀等地质灾害的影响而发生管道位移、形变的问题,开发了一种高精度的惯性导航系统对管道实施内检测,从而获得检测器的位置、姿态信息,并在此基础上,提出了管道弯曲应变及位移的计算方法。在计算位移时,针对管道计算轨迹发散的问题,提出了使用外部特征点修正误差的方法;在计算管道位移或弯曲应变的变化量时,针对重复检测中存在里程差的问题,提出了将固定长度管道数据对齐后再做对比的方法。通过现场实际应用验证了该系统及方法的可行性及检测精度,为管道事故的预防和合理维护提供了科学依据,对保证冻土区长输油气管道的安全运行具有现实意义。

The pipelines in permafrost zones are prone to displacement and deformation due to the effect of geologic disasters （e.g. thaw settlement and frozen swelling）. In order to deal with this problem, a high-precision inertial navigation system was developed to perform internal inspection on pipelines, so as to acquire the position and attitude information of detectors. And based on this, the pipeline bending strain and displacement calculation methods were developed. When the pipeline displacement is calculated, a method to correct errors by using external characteristic points is proposed to deal with the divergence of pipeline calculation trajectory. When the variation of pipeline displacement or bending strain is calculated, it is proposed to do the comparison after the data of pipelines with fixed length is aligned, so that the mileage difference of repeated testing can be eliminated. The feasibility and inspection precision of this system and method are verified through the field application, It provides the scientific basis for pipeline accident prevention and reasonable maintenance. And it is of actual significance to the safe operation of long-distance oil and gas pipelines in permafrost zones.